The decision by Japanese airlines not to comply with Beijing's order to report flight plans before entering the newly established air defence identification zone (ADIZ) may fuel tension between the two countries, but passenger safety will not be compromised.
Technically speaking, whether or not the airlines report their plans to Beijing is a mere gesture.
All civilian aircraft are visible to radars across the globe as they have to report their position and altitude to different flying information regions (FIRs) covering one authority to another so as to maintain sufficient separation between them.
"The military can listen in on all the aircraft's identity and location so there is no need for airlines to provide separate information for Beijing to maintain safety," said Peter Lok Kung-nam, a former director of civil aviation in Hong Kong.
The air defence identification zone over the East China Sea declared by Beijing requires all planes to file flight plans to the Foreign Ministry or the Civil Aviation Administration of China and respond to the authority when they are passing by. China's armed forces would adopt defensive emergency measures against unidentified aircraft, the notice read.
"Airlines could not fall into the unidentified category as each aircraft flown is documented and its flight plans have already been approved by the civil aviation department," said Wang Yinsheng, director of the Aircraft Owners and Pilots Association of China.
Japan Airlines, All Nippon Airways and Peach Aviation stopped reporting to the mainland authorities from yesterday under orders from the Tokyo government.
The Scheduled Airlines Association of Japan confirmed there would be no impact on the safety of passengers even if flight plans were not submitted to China.
Other carriers, such as Singapore Airlines and China Airlines, have complied with the rules. "Some of our flights fly over the airspace and we have been filing our flights plans with the Chinese authorities," said a Singapore Airlines spokesman.
The Taiwanese Civil Aeronautics Administration also urged its airlines to comply with the rules to avoid being classified as unidentified aircraft.
Cathay Pacific said its operations were unaffected, without saying whether it was complying with the rules.